1. Field of the Invention
The present invention relates to a cooling and lubricating composition, and more specifically to a composition which is a mixture of (a) a mixture of monobenzylated ethyl benzene, dibenzylated ethyl benzene and tribenzylated ethyl benzene, and (b) a polyphenyl ether.
2. Description of the Prior Art
The use of alkylbenzenes and their derivatives in lubricating oils is well known. See for example, U.S. Pat. Nos. 3,785,974; 4,555,352; 4,642,730; and Japanese Patent No. 37-13177; Canadian Patent No. 539,809 and U.S.S.R. Patent No. 228,215. Alkylbenzenes generally provide coolant properties to lubricants.
Polyphenyl ethers have been used in lubricants for their thermal and oxidative stability. See for example, U.S. Pat. Nos. 3,360,467; 3,423,469; 3,510,427; 3,567,783; 3,704,277; 3,860,661 and 4,555,352; and Japanese Patent Nos. 59-4692 and 37-13177.
Japanese Pat. No. 37-13177 discloses an oil of a copolymer of p-xylylene and one of diphenylether, a, w-diphenylalkylene and/or alkylbenzene.
There is a need for high performance thermal lubricating fluids for use in high speed, high temperature generators. These fluids are required to retain their properties at operating temperatures of about 300.degree. C. and start-up temperatures below 0.degree. C.
In spite of these prior disclosures, there remains a need for a lubricating oil that has thermal stability, viscosity, at high and low temperatures retains good lubricating properties, a low pour point, superior heat transfer properties and good lubrication characteristics for use in high temperature generators and transformers.